This invention relates generally to ceiling trim systems and, in particular, to trim pieces for installation between the gaps formed between suspended ceilings and drywall partitions.
Suspended ceilings are typically constructed by suspending a series of main T-bars and cross T-bars from the main structural ceiling by hanger wires so as to form an overhead grid. Rectangular ceiling panels are then inserted into each section of the grid where they are supported by the horizontal flanges of the T-bars. This mode of construction is advantageous in that it permits the ceiling panels to be easily removed to provide access to the main structural ceiling for maintenance.
After the ceiling is installed, drywall partitions are cut to size and erected by means of fastening the partitions to metal studs or channels secured to the floor and the T-bar grid work. Since the partitions are secured below the flanges of the T-bars and the ceiling tiles rest on top of the flanges of the T-bars, this method of construction results in an aesthetically undesirable gap, at least as wide as the thickness of the flanges of the T-bars, being formed between the partitions and the ceiling tiles between each pair of T-bars. This problem and the installation process are described in detail by U.S. Pat. No. 4,587,781, which patent is hereby incorporated by reference.
U.S. Pat. No. 4,074,478 teaches the use of a drywall casing bead, having a removable tear strip. The bead is comprised of a first, vertical strip joined to a second strip so that the first and second strip form an acute included angle, with the junction between the first and second strip forming an elongate lip which provides a margin for the accumulation of masking material. A removable tear strip is joined to the second strip along a scored and weakened line so as to form a 90.degree. angle with the vertical first strip. When the tear strip is removed, an unattractive space is left between the elongate lip and the ceiling part with only the torn edged second strip extending there between. Due to the normal irregularities in the height of the wallboard partition, in the height of the ceiling grid and in the level of the floor, the height of this gap will generally vary widely along the length of the partition.
U.S. Pat. No. 4,587,781 teaches the use of a generally T-shaped trim piece including a tongue portion and a flange element to both cover the gap between wallboard partition and the ceiling panel and to provide an aesthetically pleasing trim strip along the upper edge of the partition. When installed, the tongue portion extends between the channel support behind the partition and the rear of the partition. The substantially longer trim flange element, which is substantially the same thickness as the flanges of the T-bars, extends from behind the partition at a 90.degree. angle to the tongue portion through the gap along the underside of the ceiling tile beyond the wallboard.
This trim piece is also insufficient to cover a gap between a wallboard partition and a ceiling panel due to the normal irregularities in the height of the wallboard partition, the ceiling grid and the level of the floor which vary the size of the gap to fill. Furthermore, this trim piece suffers from a number of additional shortcomings. First, the trim piece provides no suitable guide for the worker trowel or brush, thereby increasing the likelihood that paint or joint compound will be splattered on the trim flange. Second, any paint and/or joint compound which is splattered, must be scrubbed from the trim piece after the trim piece has been installed, a relatively difficult and time consuming task. Third, the trim piece cannot be removed to be refinished or replaced without tearing down the drywall partition.
Thus, there is needed an improved trim piece for suspended ceilings which is adapted to cover the wide variety of uneven gaps generally present between the wallboard partition and the ceiling panel, overcoming the drawbacks of past devices.